As a semiconductor device is highly integrated, the elements of a device should be disposed on a substrate at higher density. Because the elements are disposed at narrow distances apart, undesired interaction may occur between the elements. Such interaction degrades reliability of the device. For preventing this, Z various techniques have been proposed for separating the elements.
One technique, which disposes the elements on the SOI substrate, has been proposed as one means for electrically and/or spatially separating the elements. However, limitations that may not occur in existing bulk substrates may be presented when the elements of the device are disposed on the SOI substrate.